Summary of Core projects active during FY2019: In FY2019, the Core was used by 12 investigators from eight NHGRI branches for a number of projects as described below. Microinjections of human and zebrafish tp63 mRNA to evaluate a candidate variant by rescue of the knockout phenotype (Bailey-Wilson lab). Time-lapse imaging to determine exact time and mechanism of death in tp63 knockout fish (Bailey-Wilson lab). Microinjections of morpholinos and mRNAs to validate the role of gata2 in compensation of runx1 knockout phenotype (Liu lab) Microinjections of plasmid DNA and CRISPR reagents and fluorescent screening to test multiple conditions for efficient targeted knock-in (Burgess lab) Generation of knockout mutants for 7 genes is completed and 3 genes is in progress (Brody, Burgess, Chandrasekharappa, Liu and Muenke labs). Generation of enhancer deletion mutants for 3 genes is in progress (Liu and Muenke labs). Hands-on training to 11 users in microinjections, genotyping, WISH, imaging, tissue extraction and TUNEL staining (Brody, Burgess, Chandrasekharappa, Gahl/UDP labs). Evaluation of non-coding fragments for their role as regulatory elements by cloning and transgenesis (Wilson lab) Facilitated phenotypic characterization of knockout fish for >25 genes involved in a variety of diseases and biological processes (Fanconi anemia, leukemia, hematopoiesis, splicing, and thyroid development) by analysis of embryonic and larval phenotypes by fin clips, genotyping, TUNEL staining, WISH, imaging and histology. Performed cryopreservation of all new mutant and transgenic lines. Sequencing to genotype mutant lines with point mutations (Burgess lab). Facilitated importing and exporting fish lines for collaborations. Maintained 18 lines (WT, mutant and transgenic) by breeding and genotyping. Technology development by testing various knock-in and base editing approaches. To generate above-mentioned mutant lines, we processed 68,000 DNA samples for genotyping by fluorescent PCR using our capillary electrophoresis method and and performed 5,200 sequencing reactions.